Crusher says that the telepathic implants are connected directly to the brainstem, but Lorin says that they are connected to the cerebral cortex. Given the localization of function in the human brain, a telepathic implant in the cerebral cortex would be more intuitive. Interestingly, the superficial location of the implants would suggest connection to the brainstem, which would indeed be a prime spot for inducing nausea, as seen in the episode. This ambiguity in neuroanatomy technobabble continues a Star Trek tradition of referring to the brain as the cerebral cortex even though it is just one albeit very large area of the brain.